Five Level MCHB Hybrid Active Power Filter for Harmonics Mitigation

The presence of nonlinear loads significantly deteriorates power quality. With the rapid advancement of power electronics, particularly power semiconductor devices, the prevalence of nonlinear loads has expanded considerably. These loads generate harmonics in the power system and lower the power factor, thereby increasing the demand for reactive power. To address these issues, both active and passive power filters have been extensively implemented in distribution networks. A hybrid active power filter, which integrates the advantages of both filtering types, offers enhanced performance and effectiveness. At the core of this system lies a voltage source inverter, whose performance directly influences the overall efficiency of the filter. This paper proposes a modified cascaded H-bridge (MCHB) five-level inverter configuration for the realization of a hybrid active power filter. A MATLAB-based simulation model has been developed to validate the proposed control approach, which utilizes a instantaneous reactive power (pq) theory and PI controller. The simulation results demonstrate effective harmonic suppression and reactive power compensation. The proposed MCHB structure effectively reduces inverter size and cost of the hybrid active power filter.